Coke oven door locking means



Aug. 5, 1941,

E. GRASSHOFF COKE ovEN no oR LOCKING MEANS 'Filed Feb. l5, 1939 2 Sheets-Sheet l INVENTOR ETHHHRQ Gknam E. GRAssH'ol-F 2,251,541

COKE ovEN DOOR LOCKING MEANS Aug. 5, 1941.

Filed Feb.. l5, 1939 2 Sheets-Sheet 2 ELE/MM ATTORNEY Patented Aug. 5, 1941 COKE OVEN 900B. LOCKING MEANS Eberhard Grassho, Bochum, Germany, assigner,

by mesne assignments, to Fuel Refining Corporation, a corporation of Delaware Application February 15, 1939, Serial No. 256,462 in Germany March 31, 1938 (Cl. 21R-248) S Ciaims.

The present invention relates to doors employed as removable gas tight closures for openings in coking chamber Walls. While the invention is of especial value for use in connection With so-called self-sealing coke oven doors employed to close the ends ofthe coking chambers, of horizontal coke oven batteries, the general principle of the invention may also be used with advantage in connection with the much smaller chuck or leveling bar doors, normally closing the charge leveling bar openings, customarily provided in the main coke oven doors at the pusher side of a horizontal coke oven battery.

In modern practice, each self-sealing coke oven door employed to close the end of a horizontal coking chamber, is customarily pressed against the associated door frame so as to establish a sealing pressure between the door frame and a iiexible metallic sealing member of the door, of many thousands of pounds. In some cases, the sealing pressure is 15 tons or more. Such a coke oven door is customarily locked in place, by means of one or more locking'bars, usually two, mounted on each door, and having their ends in engagement with retaining hook extensions of the door frame.

In the most usual construction, the connection between each door and locking bar comprises a nut and screw, which are relatively rotated to vary the eiective length of the connection. OW- ing to frictional resistance and the heavy sealing pressure required, some practical diiculties have been experienced in effecting the proper connection length adjustment required in each door closing operation. In another commercial type of door, the door and locking bar connection includes a spring, the tension of which establishes the sealing pressure, and which is put under compression to neutralize the sealing pressure by door handling machinery yspecially constructed for the purpose.

The primary object vof the present invention isto provide a door of the above mentioned kind, with a simple and effective door and locking bar connection ofsuch character that the Weight of the door may automatically establish the sealing pressure by a sort of toggle joint action effected lin the iinal portion of each door closing operation. In its preferred form, the connection between each locking bar and the door, comprises a link or strut connected at one end to the door to turn relatively thereto about a horizontal axis, and normally extending outwardly and downwardly away from the door at a small angle to the horizontal and'having its otherend connected to the locking bar and which is adapted to operatively engage stationary door retaining means prior to the nal small down movement of the door by which causes the strut is adjusted into a position in which it is more nearly horizontal than when the retaining hooks were initially engaged. To permit of a suitable calibrating adjustment cf the length of each such strut, the latter may advantageouslyfcomprise nut and screw connected sections. Advantageously, also, the strut may comprise sections connected by a spring, the tension of which automatically limits and determines the sealing pressure established when the door is closed.

With a door provided with the improved locking means, all that is necessary toestablish and release the sealing pressure is `to permit the door to move down under the action of gravity, in the iinal portion of thedoor replacing operation, and to give the door a small up movement in the initial portion of each door removing operation. Such movements may be given the door byany of the existing door machines kwhich include, as most of Ythem do, aldoor engaging hook 1ever, and means for giving the hook end of the lever an up movement to engage and lift the door, and a down movement to disengage the door after the latter .has 'been inserted in the mouth of the oven.

In the use` of the invention in connection with a leveling bar, or chuck, door, the latter may be provided with a locking bar similar in the manner in which it is connected to the door and operates, to the locking bars of the improved coke oven doors previously described. In its preferred form, each chuck bar door is provided with a bail, or shoulder,.part, adapted to be engaged by the hook portion of a chuck door operating mechanism. The latter isadvantageously mounted on the pusher machine employed to push the finished cokeout ofthe -coking chambers and provided with a levelling bar mechanism for ,levelling the coal charges in the coking chambers. Said `mechanism is adapted to move the chuck door upwardto open'the leveler bar opening, and to permit said door to move down into the portion in which itcloses and seals said opening. The chuck door sealing action is eiectedras in the case of the improved main coke oven doors, by the weight of the door, which straightens out the toggle joint connection between the chuck door and vits locking bar, when the door is permitted to move down into its closed position.

The various features of novelty which characterize my invention are pointed out with particularity in the claims annexed to and forming a part of this specification. For a better understanding of the invention, however, its advantages, and specic objects attained with its use, reference should be had to the accompanying drawings and descriptive matter in which I have illustrated and described preferred embodiments of the invention.

Of the drawings- Fig. 1 is a vertical section through the coke side doorway portion of a coking chamber, and the corresponding door, the section being taken on the line I-I of Fig. 3;

Fig. 2 is a partial vertical section, taken on the line 2-2 of Fig. 3;

Fig. 3 is a horizontal section taken on the line 3 3 of Fig. 1;

Fig. 4 is a vertical section through the pusher side doorway and door of a coking chamber, showing a portion of a pusher machine with a chuck door operating mechanism mounted thereon;

Fig, 4A is an enlarged reproduction of a portion of Fig. 4;

Fig. 5 is an enlarged reproduction of another portion of Fig. 4;

Fig. 6 is a partial horizontal section on the line 6-6 of Fig. 5; and

Fig. 7 is an elevation, taken at right angles to Figs. 5 and 6, of the portion of the apparatus shown in Figs. 5 and 6.

In Figs. l, 2 and 3, I have illustrated the use of the present invention in connection with a self-sealing door employed to close the coke side end of one of the coking chambers A of a horizontal coke oven battery A, of the general type customarily employed throughout the world in the production of metallurgical coke. The doorway is surrounded by a metallic door frame B provided with an outwardly facing sealing surface B extending transversely to the axis of the oven. The door shown as closing the doorway comprises an inner plug section C extending into the coking chamber, an intermediate iiexible metallic sealing section D, and a rigid metallic outer section E. The plug section D of the door comprises a vertically elongated mass of re bricks or other refractory material resting on a metallic supporting member C', connected to bracket portions E' of the rigid outer door section E.

The refractory plug section material is shown as reinforced by vertical metallic rods C2 connected at their lower end to the bracket C and at their upper ends to a metallic part C3, through which the upper end of the plug section is mechanically connect-ed to an upper bracket portion -E2 of the outer door section. As shown, the iexible sealing section D of the door comprises a metal plate body portion which extends across the doorway, with portions between the bracket C and brackets E', and between the bracket E2 and part C3. The body portion of the sectionD is provided at its margin with an inwardly extending flange portion D', the inner edge of which abuts against the sealing surface B of the door frame, in the closed position of the door. The rigid outer section E is provided with the usual screws E3 parallel to the door axis, which engage the sealing member D adjacent its margin at points distributed along said margin, and by Itheiradjustment give the sealing edge D the contour for proper engagement with sealing surface B' all around the doorway.

In so far as above described, the self-sealing coke oven door shown in Figs. 1, 2 and 3, includes nothing now novel with me, but is illustrated merely as one known form of self-sealing coke oven door with which the present invention may be used with advantage.

The door shown in Figs. l, 2 and 3 is locked in its closed position by means of upper and lower locking bars F, at the outer side of the door and having their ends in engagement with retaining hooks G secured to the door frame B and having an inwardly and upwardly facing surface for engagement by the corresponding locking bar. In respect to the form and general purpose of the locking bars F and retaining hooks G, the construction shown in the drawings does not differ from prior practice, but the means provided in accordance with the present invention, to connect the locking bars to the rigid outer section E of the door, are novel in construction and operation.

As shown, each locking bar is connected to the door by a strut H which has one end pivotally connected by a horizontal shaft I to a portion E4 of the rigid outer door section E, to turn about a horizontal axis, and which extends outwardly and downwardly from the door, and which has an outer end portion H on which the locking bar is mounted.

In the preferred construction illustrated, the outer end portion H of each strut is connected by a plate spring H2 to an intermediate rigid portion H3 of the strut comprising a threaded portion screwed into a threaded socket in a section of the strut through which the pivot shaft I extends. As shown, the outer strut portion H is provided at its outer end with a squared nut for engagement by a wrench through which said portion may be rotated about its own axis, to thereby increase or decrease the normal distance between the locking bar and the axis of the shaft I. The spring H2, as shown, is formed by two coaxial dished discs connected at their peripheries and having their concave sides adjacent one another.

As shown, the gravity induced counter-clockwise movement of each locking bar about the corresponding shaft I, when the door shown in Fig. 1 is raised in the door removing operation, is limited by shoulders or projections E5 on the door section E. Said shoulders are arranged to hold the locking bars in proper position for their initial engagementv with the hooks G, in each door replacing operation.

The-rigid outer door section E comprises a transverse shoulder portion E6 adapted for engagement by the hook end of the door lifting lever K of a suitable door machine mechanism, shown in Fig. 1 as comprising a vertically eX- tending member K provided with a lower door engaging part K2 which serves to prevent the door from tilting clockwise under the action of gravity when lifted by the lever K. Ordinarily, the member K will be mounted on a carriage movable longitudinally vof the battery, at the pusher side of the battery said carriage usually being the pusher machine carriage, and will be movable relative to its supporting carriage in the direction of the axes of the coking chambers by mechanism of known type.

In the closed position of the door, shown in Figs. 1,. 2 and `3aportion ofthe weight of the door will be supported by each strut H, which is thus caused to transmit a longitudinal, thrust force to the corresponding pair of hooks G. Advantageously, the two struts are adjusted to have such relative lengths that each will support approximately half of the entire weight of the door. The thrust transmitted by each strut to the corresponding pair of retaining hooks G, comprises a horizontal component which, with the relatively small strut inclination to the horizontal shown in Fig. l, will be several times the entire weight of thedoor, assuming that approximately half the weight of the door is supported by each strut. The magnitude of each horizontal component may be increased or decreased, by respectively decreasing or increasing the inclination to the horizontal of the corresponding strut H.

The reactive force equal to the sum of the horizontal components of the forces transmitted by the two struts H, constitutes the sealing pressure with which the sealing edge D is` pressed against the sealing surface B. Since the weight of a coke oven door of the type shown is ordinarily of the order of 21/2 tons, it is thus readily possible to obtain a suitabie sealing pressure of 15 tons or so, by adjusting the effective length of the struts H so that they will have the proper inclination to the horizontal, when the door is in its closed position.

Only a relative minute vertical door movement is required to establish and to eliminate the sealing pressure, so that during the major portion of the vertical movement of the door required for the movement of the locking bars between their lowermost level, and the level at which they clear the tops of the corresponding retaining hooks G, the sealing edge D is not pressed against the sealing surface B by any portion of the normal door locking force.

As shown in Fig. 4, at the pusher side of the battery the end of the coking chamber A is closed by a door comprising plug, sealing and rigid outer sections CA, DA, and EA, respectively, difering in form from the sections C, D

and E, respectively, of the coke side door shownV in Figs. 1 3 only as a result of the provision of the pusher side door with a levelling bar opening surrounded by a door frame L. The latter, as shown, is in the form of a horizontally disposed open ended box, the outer end surface L' of which serves as a sealing surface for engagement by the sealing edge portion of the chuck door M which normally closes the leveller bar opening. As shown, the door frame L extends through an opening in the body plate portion of the sealing section DA and is provided with an outwardly extending flange L2 in overlapping relation w'lth, and secured to said body plate portion. While the door frame member L may be directly attached to the outer door section EA, as shown it is connected to the latter only through the sealing section of the door.

The chuck door M is provided with a locking bar N, which in the closed position of the door engages retaining hooks O, connected to and extending outwardly away from the frame L at opposite sides of the latter. The connection between the door M and the locking bar N comprises a strutlike member P, shown as connected to the door M adjacent the center of the latter by a horizontal pintle shaft P', and lformed With a slotted opening in which the central portion of the bar N extends. The effective length of the strut connection between the shaft P' and the locking bar N is advantageously adjustable in length as is the case With the locking bar connections shown in Figs. l to 3. As shown, the adjustment of the strut P is effected by means of a Screw P2 threaded through a threaded opening in an outer yoke portion of the member P, and having its inner end swivelled in the central portion of the locking bar.

As Will be apparent, when the door M is allowed to move down into its closed position, its weight causes it to exert a toggle joint thrust action through the strut P on the locking bar N, whereby the sealing edge M of the door is pressed against the sealing surface L With the desired sealing force. The sealing pressure thus established, is released as soon as the door M is given a slight upward movement.

In Fig. 4, the conventionally illustrated pusher machine Q provided with a charge expelling ram Q', supports a charge levelling bar Q2 and mechanism (not shown) for moving the bar Q2 into the oven chamber through the door frame L when the door M is moved out of the way. As shown, the machine Q also includes mechanism for giving the chuck door M opening and closing movements.

As diagrammatically illustrated, the mechanism for opening and closing the chuck door comprises a lever R and means for giving its door engaging end R horizontal movements at or about level at which it is shown in full lines in Fig. 4;, into and out of operative engagement with the door and up and down movements While in operative engagement with the door between its positions shown in full and dotted lines in Fig. 4. When in its dotted line position, the lever end R' is adapted to hold the door M above the path of movement of the leveller bar, as the latter moves into and out of the oven chamber through the leveller bar opening.

As shown, the lever end R is in the form of a hook, and the door M is provided at its upper edge with a bail like part M2, into and out of which the hook R may be horizontally moved when at its lower level, andwhich is engaged by the hook end R when the latter is raised after being entered in said bail.

The mechanism for giving the lever R its required operative movements may take Various forms. As diagrammatically illustrated, the fulcrum of the lever R is formed by a link or strut member S, which has its upper end pivotally connected to the lever R between the ends of the latter, and has its lower end pivotally connected to the frame Work of the pusher machine Q. Associated with the lever R are means for moving the end of the lever remote from the hook R', along a path comprising generally horizontal and generally vertical portions. The horizontal movements of the end R effecting its operative engagement with, and disengagement from the door, and its vertical movements lifting the door up from and returning it to its closed position. As diagrammatically shown, said path of movement is determined by the form of a cam slot T in a stationary cam block T, which receives a transverse projection from the lever R shown as formed by one end of a pin R2.

The pin R2 is caused to move along the slo't T by a crank arm U carried by a shaft U', and formed with a radially extending slot U2, into which a portion of the pin R2 is received. In the particular arrangement shown, the hook end R may be withdrawn from the bail M2, by a counterclockwise movement of the arm U through an angle of about from its position about the shaft U, and angular movements of the .i

shaft U in excess of those required to give the hook end of the lever R its necessary movements will do not harm.

In the construction shown in Figs. 4-7, integral projections M3 provide shoulders arresting down y movement of the locking bar relative to the door, when the latter is out of its closed position.

Whether the invention is used in connection with chuck doors or with coke oven doors closu ing the ends of coking chambers, it is essential to the contemplated operation that the door, and the sealing surface engaged by it should be generally vertical or upright, though some departure of the door and sealing surface from the vertical will involve no significant interference with the toggle sealing action effected by the weight of the door.

While in accordance with the provisions of the statutes, I have illustrated and described the best forms of embodiment of my invention now known to me, it will be apparent to those skilled in the art that changes may be made in the form of the apparatus disclosed without departing from the spirit of my invention as set forth in the appended claims and that in some cases certain features of my invention may be used to advantage Without a corresponding use of other features.

Having now described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. Apparatus adapted to form a removable gas tight closure for an opening in a coke oven structure having a vertically disposed sealing surface surrounding said opening and having door retaining means displaced outwardly from said sealing surface, said apparatus comprising in combination, a door having sealing means at one side and a locking bar at the other side of the door, and connection means pivotally connecting said bar to said' door for movement of said bar relative to said door about a horizontal axis between said locking bar and sealing means, said sealing means and bar being adapted to operatively engage said sealing surface and a portion of said retaining means, respectively, with said axis between said surface and portion, and at a distance above said portion which is substantially smaller than the radial displacement of said portion from said axis and with said bar and connection means forming a strut supporting the weight of the door and holding said sealing means against said sealing surface with a sealing pressure exceeding the weight of the door, said door being vertically movable relative to said eolie oven structure under the action of gravity downward into the position in which said sealing pressure is established, as specied, from an upper position in which said locking bar engages said door retaining means and said sealing means engages said sealing surface without establishing said sealing pressure.

2. Apparatus as specified in claim 1, in which the connection means between the door and the locking bar is adjustable in length to vary the radial distance between said axis and the portion of the locking bar operatively engaging the door retaining means.

3. The combination with apparatus as specified in claim 1, of means holding said bar while it is being moved into operative engagement with said retaining means, at a small distance below its position relative to the level of said axis when said door is in its closed position.

4. The combination with a door frame located at the end of a horizontal coking chamber and provided with an outwardly facing sealing surface surrounding the coling chamber and with door retaining hooks at opposite sides of the coking chamber and displaced outwardly from said sealing surface, of a self-sealing coke oven door comprising an inner plug section adapted to extend through said door into the coking chamber, a rigid outer metallic section, and a iiexible metallic sealing section adapted to extend into overlapping engagement with said sealing surface, a locking bar, connection means pivotally connected to said outer door section to turn relatively thereto about a horizontal axis between said locking bar and sealing section and adapted to operatively engage said hooks in the closed position of the door at a level slightly below the level of said axis, and thereby, in conjunction with said bar, forming a strut supporting the weight of the door and holding said sealing means against said sealing surface with a sealing pressure exceeding the weight of the door, said door being vertically movable relative to said coke oven structure under the action of gravity downward into the position in which said sealing pressure is established, as specified, from an upper position in which said locking bar engages said door retaining hooks and said sealing means engages said sealing surface without establishing said sealing pressure.

5. The combination with a metallic door frame surrounding a leveling bar opening in the end wall of a horizontal coling chamber, said frame having an outwardly facing sealing surface and having door retaining hooks at the opposite sides ofsaid opening and displaced outwardly from said surface, of a door vertically movable between a lower position in which it closes said opening and an upper position in which it is above the path of movement of a leveling bar extending through said opening, said door being formed with a metallic sealing portion adapted for gas tight joint engagement with said surface, and a locking bar pivotally connected to said door at the outer' side of the latter to turn relatively to the door about a horizontal axis between said locking bar and sealing portion and adapted to engage said hooks at a level slightly below that of said axis when said sealing means engage said surface, and to thereby limit the gravitational down movement of the door.

6. The combinati-on with a metallic door frame surrounding a leveling bar opening in the end wall or" a horizontal coking chamber, said frame having an outwardly facing sealing surface and having door retaining hoolzs at the opposite sides of said opening and displaced outwardly from said surface, of a door vertically movable between a lower position in which it closes said opening and an upper position in which it is above the path of movement of a leveling bar extending through said opening, said door being formed with a metallic sealing portion adapted for gas tight joint engagement with said surface, and a locking bar pivotally connected to said door at the outer side of the latter to turn relatively to the door about a horizontal axis between said locking bar and sealing portion and adapted to engage said hooks at a level slightly below that of said axis when said sealing means engage said surface and to thereby limit the gravitational down movement of the door, and mechanism for moving said door between its upper and lower positions.

'7. The combination with a horizontal coke oven battery and associated pusher machine, of metallic door frames surrounding leveling bar openings in the pusher side end walls of the coking chamber of said battery, each of said frames having an outwardly facing sealing surface and having door retaining hooks at the opposite sides of said opening and displaced outwardly from said surface, doors for said openings each vertically movable between a lower position in which it closes the corresponding opening and an upper position in which it is above the path of movement of a leveling bar extending through said opening, each door being formed with a metallic sealing portion adapted for gas tight joint engagement with the said surface of the corresponding frame and a locking bar for each door pivotally connected thereto at the outer side of the door to turn relatively thereto about a .horizontal axis between said locking bar and sealing portion and adapted to engage the corre- 'doors between its open and closed position.

8. Apparatus adapted to form a removable gas tight closure for an opening in a coke oven structure having a vertically disposed sealing surface surrounding said opening and door retaining means displaced outwardly from said sealing sur' face, said apparatus comprising in combination a door having sealing means at one side and a locking bar .at the other side of the door, connection means pivotally connecting said bar to said door for movement of said bar relative to said door about a horizontal axis between said locking bar and sealing means, said sealing meians and bar being adapted to operatively engage said sealing surface and a portion of said retaining means, respectively, with said axis between said surface and portion, and at a distance above said portion, which is substantially smaller than the radial displacement of said por-tion from said axis, said connection means including a spring which is put under tension, in the closed position of the door by weight of the door, and thereby determines the sealing pressure with which said sealing means engages said sealing surface.

EBERI-IARD GRASSI-IOFF. 

